Method of ramming sand molds.



H. P. MACDONALD.

METHOD OF RAMMING SAND MQLDS APPLICATION FILED 0012.29, 1912.

1,083,546. Patented Jan. 6, 1914.

2 SHEETS-SHEET 1 WITNESSES:

INVENTOR.

M aim M COLUMBIA PLANOGRADH c0. WASHINGTON. D. c.

H. P. MACDONALD. METHOD OF RAMMING SAND MOLDS.

APPLICATION FILED OCT. 29, 1912. 1,083,546. Patented Jan. 6, 1914,

2 SHEETSSHEET 2.

WITNESSES: I

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tUNllTED STATES PATEN :QFFEWE.

HARRY P. MACDONALD, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO THE SNEAD & CO. IRON WORKS, 015 JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

METHOD OF RAMMING SAND MOLDS.

To all whom it may concern Be it known that I, HARRY P. MACDONALD, a citizen of the United States, residing at Montclair, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Methods of Hamming Sand Molds, of which the following is a specification.

This invention relates generally to a method of ramming sand molds and particularly to a method wherein the ramming or compressive element is a heavy roll or equivalent movable body. The apparatus shown in the drawings is of the same class as that illustrated in my co-pending application Ser. N 0. 723,684 filed Oct. 3, 1912. It has for its primary objects: the provision, of an improved method of ramming the sand whereby the sand is uniformly packed and may be packed to any desired degree of hardness; and the provision of an improved method whereby the sand is packed uniformly throughout the flask by a ramming element through an interposed ramming medium, portions of which are successively engaged by the ramming element. These, together with such other objects as may hereinafter appear or are incident to my invention, I accomplish by a method illustrated by the construction disclosed in the accompanying drawings, wherein Figure 1 is a longitudinal section through a ramming machine showing the application of my invention thereto; Fig. 2 is a section of the device shown in Fig. 1 taken on the line IIIIII of said figure, and Fig. 3 is a plan view of Fig. 1.

In order to arrive at a better understanding of my improved method, a description of the apparatus will be first given. Referring to Fig. 1, it will be seen that I have shown a pattern plate support or table 7 which is suitably supported from the foundry floor by means of a framing 8 and which is adapted to carry the pattern 9 and support the flask 10. The pattern shown is of an interrupted character and the flask 10 is provided with transversely extending bars or plates 11 which hold the sand in the flask in operations succeeding the ramming operation. An upset or frame 12 for retaining the sand in position over the flask during the ramming operation is supported on the Specification of Letters Patent.

Application filed October 29, 1912.

Patented Jan. 6, 1914. Serial No. 728,433.

flask and is maintained in proper alinement by means of lugs 13.

The ramming element proper is a heavy roll 14 mounted in the yoke 15 of a long op erating arm 16, the roll when in operative position being supported in the platform or frame 17 which is located adjacent the pattern plate support and its supporting framework. The sand is rammed in the flask by the passing of the roll over an interposed ramming medium which is preferably sectional and of a flexible character. This ramming medium comprises what may be termed a pad composed of a plurality of bars 18 which are secured together by flexible ropes or cables 19 in such manner as to have relative vertical movement with re spect to one another whereby a bending or wave-like movement of the pad takes place as the roll is passed over its upper surface. The bars are spaced apart by means of washers 20. As will plainly appear from the drawings, the pad is placed in the upset 12 and rests upon the sand. In order to transfer the roll from the platform 17 to the top of the pad and maintain the pad in proper position in the upset, I provide bridging members 21 which are pivoted at their inner ends to the first bar of the pad and have at their outer ends hooked portions 22 engaging recesses 23 cut into the platform 17. The members 21 thus serve as a bridge on which the roll rides from the platform to the pad and also as a means for pressing down the first bar of the pad precedent to its engagement by the rolls, thus preventing the roll from tipping the bars.

The operation of the apparatus is as follows: After the flask, pattern and upset are properly placed, the flask is filled with sand which is struck off at any desired depth, preferably on a level with or slightly below the top of the upset. The pad is then positioned and the roll is advanced from the platform riding onto the pad from off the bridging members. As the roll advances the bars of the pad are successively engaged and driven downwardly compressing the sand, the entire weight of the roll coming down on one or more of the bars at a time. From this it will be apparent that each bar presses down with the same intensity, with the result that the sand is uniformly packed throughout the flask. It will also be seen that inasmuch as the entire compressive force of the roll isapplied to one or at the most, not more than several of the bars at a time, the weight of the roll is applied to the best advantage over successive restricted areas, thus permitting of the use of a lighter roll while at the same time securing superior results. This feature lends ease and simplicity to the entire operation. By Varying the depth of the sand in the flask any desired degree of hardness of the packed sand can be obtained.

It will appear from the foregoing that my improved method, broadly stated, contemplates the ramming of the sand by a passive ramming element resting on the sand by passing over the passive element a compressive active ramming element, and that specifically stated, it contemplates the ramming of the sand by rolling a heavy roll or similar compressing element over a sectional passive ramming member, preferably flexible in character, which rests on the sand.

It will be seen that an operation of this character is adapted to a wide range of work, involving the use of flasks of different sizes and shapes, which can all be rammed with one roller and a number of flasks rammed successively at each stroke of the roller.

This can be accomplished readily and at small expense by simply making suitable pads and sand frames for the different sizes and shapes of flasks and designs of patterns.

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent is the following: V

1. The herein described process of ramming sand molds which consists in supporting on the sand a plurality of passive ramming elements of comparatively small width and placed closely together, the said elements having relative substantially vertical movement of translation, and then in advancing a compressing ramming element successively over the passive elements.

2. The herein described process of ramming sand molds which consists in supporting on the sand a passive ramming element comprising a plurality of relatively thin bars placed on edge and close to one another and having relative substantially vertical movement of translation and then in advancing a ramming roll over the bars.

3. The herein described process of ramming sand molds which consists in supporting on the sand a flexible passive ramming element, the sections whereof are placed closely adjacent to each other and have relative substantially vertical movement of translation, and then in passing a ramming roll over the sections successively.

In testimony whereof I have hereunto signed my name in the presence of the two subscribed witnesses.

HARRY P. MACDONALD.

Witnesses:

J. F. ARNOLD, C. C. GREENLEAF, J r.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

